Composition for cleaning and lubricating abrasive surfaces



C. M. MYERS Nov. 1, 1966 COMPOSITION FOR CLEANING AND LUBRICATINGABRASIVE SURFACES Filed June 2. 1960 United States Patent 3,282,665COMPOSITION FOR CLEANING AND LUBRICAT- ING ABRASIVE SURFACES Charles M.Myers, Chicago, 11]., assignor, by direct and mesne assignments, toThomas G. Poulakidas, Chicago,

Filed June 2, 1960, Ser. No. 33,550 1 Claim. (Cl. 51304) This inventionpertains to improvements in a method for grinding and polishing metal bythe use of an improved polishing composition.

More particularly stated this invention relates to a method for grindingand polishing metal by the use of an abrasive surface moving at highspeed and coated with ma polishing or surfacing composition, including alubricating ingredient and also including a high percentage of a highlyvolatile solvent for the lubricating inlgredient. The use of such acomposition in the practice of the improved method prevents thepolishing composition from becoming dry on the abrasive surface beforethe lubricating portion of the polishing composition is of the desiredconsistency to enable the desired polishing action. The periodicapplication of additional polishing composition to the abrasive surfaceduring the polishing operation enables the solvent present in the addedcomposition to loosen the excessively dried lubricant and the abrasiveParticles and the metal particles absorbed by the dried lubricant whichhas become impacted or loaded into the abrasive surface and causes thethus loaded material to be discharged or unloaded to maintain theabrasive surface clean and well lubricated.

This invention also pertains to an improved polishing composition,particularly well adapted for use in the mentioned improved method, andwhich improved polishing composition includes, as essential ingredientsthereof, a lubricant for the abrasive surface, a penetrating ingredientfor maintaining the cutting efliciency of the abrasive surface and ahighly volatile and noninflammable solvent tor the lubricant.

This invention also relates to the improvement in the method forcompounding or producing the improved polishing composition and theimprovements in polishing apparatus well adapted for the efiicientpractice of the improved method of polishing and for the efficient useof the improved polishing composition.

In the operation of grinding and polishing apparatus, such as, forexample, grinding and polishing latches equipped with cushioned contactwheels and abrasive coated polishing b'elts driven at high speeds, it iscommon practice to soak a new and invariably stiff polishin'g belt Withkerosene or like material to soften the belt to enable the efficient useof the belt on the cushioned contact wheel, and also to coat theabrasive surfac'e of the belt with a grease-like lubricant, as forexample, tallow or compounds of similar lubricants. The meltingtemperature and solidifying characteristics of tallow and thelubricating qualities thereof, adapt it well for such use. Thesolidified tallow enables the operator to regulate the cutting depth ofthe abrasive surface of the belt by controlling the amount of tallowadded to the surface of the belt. However, tallow also possesses theundesirable characteristic of loading the abrasive surface, particularlywhen the tallow absorbs large quantities of powdered abrasive and metalparticles, thereby to form a substantially solid material impacted intothe spaces between the abrasive particles in a substantially hard layer,thereby causing the belt to become very stiff, and also causing the beltto lose its cutting efiiciency. When a belt is thus loaded with suchimp-acted material it normally becomes necessary for the operator toeither ice stop the polishing apparatus and clean th'e belt or replacethe belt or to apply excessive pressure to the work piece beingpolished. The application of such excessive pressure to the work piecewill immediately result in undue Wear of th'e abrasive surface of thebelt, possible damage to the work piece due to excessive friction, andundue wear of the backing material of the belt, thereby decreasing theeffective life of the belt.

There are, of course, numerous varieties of metal polishing compounds onthe market intended for use in the commercial polishing of metalarticles by the use of abrasive coated disks, belts, drums and abrasivewhee-ls. However, the common complaint respecting such compounds is thatthey tend to load the abrasive surface, th'e-reby impairing thepolishing efficiency of the abrasive surface and decreasing the usefullife of the polishing element.

It is therefore one of the prime objectives of this invention to providean improved method for the grinding and polishing of metal by the use ofan improved grinding and polishing composition, whereby the nec'essarylubricant is provided on the abrasive surface in a condition whichpermits the operator to obtain the desired consistency of the lubricant,whereby to satisfactorily regulate the cutting depth of the abrasivesurface, whereby to automatically unload the used lubricant when it hasbecome too dry for satisfactory use while the grinding and polishing.continues, and whereby to maintain the clean and sharp cuttingcharacteristics of the belt which are commonly associated with a newabrasive surface.

Another objective of this invention is to provide an improvednoninfiammable and substantially nontoxic grinding and polishingcomposition including a lubricant and a cutting agent and a highpercentage of a highly volatile and noninflammable solvent for thelubricant, well adapted to lubricate an abrasive surface in such amanner as to enable an operator to choose the desired consistency of thelubricant during the polishing operation for the performance of certainaspects of the polishing operation and also well adapted to maintain theabrasive surface at its maximum cutting efiiciency and also well adaptedto maintain the abrasive surface clean and free of normal loading of theabrasive surf-ace with lubricating material which has absorbed particlesof abrasive and particles of metal.

Another objective of this invention is to provide an improved method forthe compounding or blending of ingredients of a polishing compositionincluding a greaselike or fat-like substance, a hydrocarbon mixture, anda noninflammable and highly volatile solvent for the fatlike orgrease-like substance.

A still further objective of this invention is to provide an improvedgrinding and polishing apparatus which is provided with readilycontrollable composition applying means for applying a grinding andpolishing composition including a highly volatile solvent and agrease-like lubricant to the abrasive surface of the polishing elementand which apparatus is particularly well adapted for grinding andpolishing metal by the use of the hereinbefore identified improvement ina method for grinding and polishing metal and for the use of thehereinbefiore identified improved grinding and polishing composition.

It will be apparent that the present invention possesses the advantageof permitting the operator of the grinding and polishing apparatus toselect the desired consistency of the lubricant for any specific aspectof the polishing operation by the addition of the improved polishingcomposition to the abrasive surface and then permitting the evaporationof the lubricant solvent to continue until the lubricant is of thedesired consistency on the abrasive surface. The present invention alsopossesses the further advantage of providing a noninflammable andsubstantially nontoxic grinding .and polishing composition which isrelatively inexpensive to make and easy to use and which has thequalities of maintaining the abrasive surface clean and sharp and welllubricated, and which composition, when used on grinding and polishingbelts, has the further advantage of maintaining the belt in soft andpliable condition. The present invention also provides an improvedgrinding and polishing composition by the use of which the operator ofthe grinding and polishing device is enabled to perform .the grindingand polishing operation with a minimum of effort and by the use of aminimum of pressure on the work piece being ground and polished, therebyreducing the required labor and increasing the useful life oftheabrasive surface. The present invention also possesses the advantageof providing a relatively simple apparatus Well adapted for the practiceof the described improved method of grinding and polishing met-ail.

It will, of course, be recognized that this invention may be embodied invarious forms without departing from the spirit thereof. The inventionwill, however, be described, without desire of limitation, with respectto an improved method of grinding and polishing metal and an improvedgrinding and polishing composition and an improved abrasive belt-type ofgrinding and polishing apparatus. Various modifications of the inventionmay suggest themselves to those skilled in the pertinent arts upon thereading of this specification and consideration of the accompanyingdrawings and appended claims. Such modifications may, however, comewithin the scope of the appended claims. Further advantages and theforegoing and other objectives and important novel and useful featuresof this invention and the specific nature of this invention will beapparent from the following description of the invention, when read inconnection with the appended claim and the accompanying drawings inwhich:

FIGURE 1, is a perspective view showing schematically the improvedgrinding and polishing lathe apparatus;

FIGURE 2, is a fragmentary vertical sectional view of an abrasive coatedgrinding and polishing belt, showing, in exaggerated manner, theimproved grinding and polishing composition applied in a thin layer overthe cutting surface of the abrasive particles; and

FIGURE 3, is a fragmentary vertical sectional view of the abrasivecoated belt shown in FIGURE 2, in which the spaces intermediate theabrasive particles are filled with solidified or dried polishingcomposition which has absorbed quantities of abrasive particles andmetal particles and which has become impacted into the abrasive surface.

Referring to the drawings, wherein like elements are identified by likenumerals, 1 represents a power unit for the improved grinding andpolishing lathe supported on base 2. Power unit 1 is provided withlaterally extending arbors 3 for drivingly supporting contact wheels 4releasably secured to the associated arbor 3 by a nut 5. Contact wheel 4is preferably provided with a resilient peripheral layer or tire 6composed, as for example, a suitable type of rubber. Belt 7 is lacedover the tire 6 of the driving contact wheel 4 and over the idler pulleyor wheel 8, adjustably mounted on base 9. Crank 10 and levers 11 and 12comprise conventional arrangements for the transverse and longitudinaland pivotal adjustment of idler pulley 8 for the adjustment of the belt7. An inverted pan-shaped vapor exhaust shroud 13 overlies the majorportion of the upper reach or portion of belt 7 and is provided with asuitable exhaust conduit 14. The forward end 15 of shroud 13 extendsclose to belt 7 immediately adjacent to the contact wheel 4 and overliesthe belt 7 transversely thereof to form a dirt shield to protect theoperator from material centrifugally discharged from belt 7. A polishingcomposition dispenser 16 is mounted on shroud 13. Dispenser 16 may be ofthe spray or of the film dispensing type and may,

for example, also be of the electrically operated or of thepneumatically operated or of the mechanically operated type. Dispenser16 is provided with a distributing nozzle 17 for distributing a spray orfilm of polishing composition, withdrawn from dispenser 16, onto theabrasive outer surface of the upper reach of the belt 7. A power unit 18is provided on the dispenser 16 usable in causing the controlleddispensing of polishing composition from dispenser 16 through nozzle 17and for driving the composition agitator 19 Within dispenser 16. Asuitable control circuit 20 for power unit 18, extends from power unit18 to a foot actuatable control element 21 mounted on base 2 at alocation convenient for use by an operator stationed at the normalposition for an operator adjacent the contact wheel 4.

FIGURES 2 and 3 illustrate fragmentary vertical sections of aconventional abrasive coated grinding and polishing belt including acloth backing member 22, which is normally stiff when new, and which hasbeen provided on its upper surface with a layer of glue 23 into which alayer of abrasive particles 24 have been set in conventional manner. Asshown in FIGURE 2, the improved polishing composition, when applied tothe layer of abrasive particles 24 forms a uniform layer over theexposed surfaces of particles 24. As shown in FIGURE 3, the surfacingcomposition, which in common practice may consist solely of tallow ortallow-like or grease-like substances, has become dry and has absorbedmany small particles of abrasive and metal, thereby producing arelatively hard compound impacted as at 26 between the abrasiveparticles 24.

In the grinding and polishing or surfacing of metal items, particularlyin those operations where both coarse and fine grinding must be or ispreferably done on the same abrasive surface to avoid making timeconsuming changes in the apparatus, it is common practice to use a hardand dry grease-like or fat-like lubricant, such as tallow or compoundsofsimilar lubricant materials which are normally shape retaining whenapplied to the abrasive surface. By the use of such lubricant, it ispossible to apply a layer of the lubricant to the abrasive surfacewhereby to cover, to the extent and depth desired, the cutting surfacesof the abrasive particles and by that procedure limit the cutting depthof the abrasive surface. The use of such lubricant, however, has thepronounced disadvantage of loading the abrasive surface, i.e. ultimatelyfilling the abrasive surface to the extent of rendering the abrasivesurface ineffective. To temporarily overcome such ineffectiveness, theoperator must apply much more pressure to the work piece being polished,with the resulting incurred wear on the abrasive surface of thepolishing element, possible damage to the work piece by burning andpossible damage to the backing element of the abrasive surface in thoseinstances where Ibelts, discs or drums are used, and possible permanentdamage to the abrasive wheel in those instances where such wheels areused and are thus lubricated. The use of such hard lubricants and thenormal resulting necessity of applying more and more pressure to thework pieces as the work progresses to accomplish the desired surfacingaction impairs the abrading characteristics of the abrasive surface dueto the fact that the abrasive surface is not maintained sharp and clean.The hard lubricant soon absorbs large quantities of abrasive particlesand metal particles and relatively solid masses of such mixtures becomeimpacted between the abrasive particles of the abrasive surface. Whensuch impacted conditions occur, and they occur regularly, it is normallynecessary for the operator, when using such conventional method ofpolishing, to stop the apparatus and either install a new abrasivesurface or thoroughly clean the dirty abrasive surface before continuingwith the polishing operation. Such cleaning operations are, ofnecessity, time consuming and necessarily costly.

The possible use of thin lubricants, such as certain hydrocarbonmixtures, as for example kerosene, or other thin oils, as the solelubricant for the abrasive surface, is not satisfactory for the reasonthat in addition to the normal fire hazard presented by the use of suchmaterials, such materials will not solidify during such use thereof topermit the operator to secure the desired layer of hard lubricant on theabrasive surface which is desired to enable the performance of certainaspects of the polishing operations and is also desirable to enable theoperator to control the depth of cut of the abrasive surface.

To overcome the above mentioned undesirable characteristics of presentlyavailable grinding and polishing compositions, the improved compositioncomprises an intimate mixture of 22.50 parts by weight of tallow, 32parts by weight of kerosene, 42.75 parts by Weight of trichloroethylene,and 2.75 parts by weight of oil of Wintergreen. In the improvedcomposition the tallow functions as a hard and dry lubricant, thekerosene functions as a liquid lubricant and cutting agent andpenetrating and dispersing agent and as a slow acting solvent for thehard lubricant and as a softener for the backing element when used oncloth or the like backed polishing belts or discs. Thetrichloroethylene, which is highly volatile, noninfiammable andsubstantially nontoxic, and which comprises a major portion of theimproved composition, functions as a rapid acting solvent for thelubricants, as a blending and dispersing agent for the ingredients ofthe com-position and as an agent to render the mixture noninflammable.The oil of Wintergreen, in addition to its lubricating function alsofunctions to impart a pleasing aroma to the improved composition.

It is of course well known that various other hard lubricants orcompounds of such materials comprise satisfactory lubricants for theconventional methods of grinding and polishing metal. Such otherlubricants, however, also possess the hereinbefore mentionedobjectionable characteristics common to tallow, as mentioned above. Someof such other lubricants are classified in the group of fatty acidesters which are also fat-like or grease-like, others are fat-like orgrease-like p-araflin hydrocarbons, etc., but as a group may beconsidered as comprising aliphatic materials. Obviously, in suchinstance where some other suitable fatty compound or grease-like orfatl'ike material is substituted for tallow in the improved polishingcomposition, then a suitable substitution may also be necessary withrespect to the rapid acting solvent for the lubricant. As mentionedabove, the important aspect of the improved composition is the inclusionof the lubricant agents having the mentioned desired characteristics asto lubricating qualities and as to hardness and the inclusion in theimproved composition of the large proportion of the highly volatilesolvent for the hard lubricant, which solvent is readily evaporable atnormal room temperatures and which solvent, for safety and healthpurposes, should be noninflammable and substantially nontoxic.

The improved grinding and polishing composition is preferably compoundedby intimately mixing discrete particles of the hard lubricant, such astallow, with the liquid hydro-carbon mixture lubricant and cuttingagent, such as kerosene, to produce a uniform blend of thoseingredients, whereupon the solvent for the hard lubricant, such astrichloroethylene, is added to the uniform blend of the hard lubricantand the liquid lubricant and intimately mixed and blended therewith.Thereafter the oil of Wintergreen or other desired aromatic oil is addedto the mixture to impart a pleasing aroma to the mixture.

In the use of the improved grind-ing and polishing composition in thegrinding and polishing of metal items on a belt-type polishing lathe,such as is illustrated in FIG- URE 1, the belt 7 is first coated with alayer of the improved composition by applying the composition to theabrasive surface of belt 7 by means of the nozzle 17 of the dispenser 16in which the composition is stored and continuously agitated by agitator19 to maintain the composition in a condition of uniform and intimatemixture. The high speed of the belt 7, which normally travels at from5000 feet per minute to 8000 feet per minute, depending upon theparticular polishing lathe, the size of the contact wheel 4, etc.,quickly discharges any excess composition from the abrasive surface ofbelt 7, and the abrasive surface of the belt is uniformly coated with athin layer of the improved composition, as generally indicated inexaggerated manner'in FIGURE 2. The operator then permits theevaporation of some of the highly volatile and rapid act-ing lubricantsolvent, which evaporation occurs extremely rapidly, due to the rapidmovement of the belt, until the consistency of the composition remainingon the abrasive surface is that desired for the particular aspect of thegrinding and polishing operation to be performed. The grinding andpolishing operation is then commenced and in a very short period of timethe hard lubricant commences to solidify and absorb quantities ofabrasive powder and metal powder as the lubricant solvent continues torapidly evaporate. As soon as the belt becomes dirty or loaded with themixture of hard lubricant abrasive powder and metal powder and the thusformed mixture becomes impacted into the abrasive surface of the belt,the operator then actuates the dispenser 16 and applies additionalquantities of the improved composition to the abrasive surface of belt 7while the polish ing operation continues. The application to belt 7 ofsuch additional quantities of the improved composition substantiallyinstantaneously loosens or dissolves the impacted and dirty hardlubricant and it is unloaded or discharged from belt 7 by centrifugalforce and the polishing operation is continued in the manner describedabove. Obviously, the above described improved method of grinding andpolishing metal items need not be performed by the use of the improvedautomatic apparatus as described, but instead may also be performedmanually by the application of the improved composition to the abrasivesurface by the careful use of swabs or similar devices.

From the foregoing description of this invention and from theaccompanying drawings, it will be apparent that this invention realizesthe introductorily enumerated objectives respecting the improvements ina method and composition for polishing metal, and the improvements.

in the method of compounding the improved polishing composition, and theimprovements in apparatus useful in the convenient practice of theimproved method of grinding and polishing metal. It will similarly beapparent that the invention also possesses the hereinbefore listedadvantages and provides new and useful and novel improvements in amethod and composition for polishing metal and method for compoundingthe improved composition and apparatus useful in the performance of theimproved method of polishing metal.

Having thus described and illustrated the above identified invention,the invention is not to be interpreted as being restricted to thespecifically illustrated and described embodiments thereof as set forthin the drawings and as hereinbefore described, except insofar as isnecessitated by the appended claim and the disclosures of the prior art.

The invention is hereby claimed as follows:

A liquid composition for application to an abrading surface for removingloading or impacted material from such surface and for cleaning suchsurface, whereby to maintain the abrading characteristics of suchsurface while simultaneously using the thus treated abrading surface incutting engagement with a work piece, consisting of an intimate mixtureof the essential ingredients thereof which are, 22 parts by weight oftallow, 32 parts by weight of kerosene, and 42 parts by weight oftrichloroethylene, said trichloroethylene being substantially nontoxicand also being highly volatile and also being noninfiammable and alsorendering the entire composition noninflarnmable, said trichloroethylenealso imparting to said composition the ability to substantiallyinstantaneously clean the abrading surface and loosen and remove theloading or impacted material therefrom when the composition is appliedto such abrading surface.

References Cited by the Examiner UNITED STATES PATENTS Ellis.

Pilgrim 513 04 Lupo 51-304 Pringle 51281 Lupo 513 06 Larsen 513 05 8Hamilton 106-8 Be'ltrarn et a1. 51135 Marsh et a1 51304 Edgemond et a151-135 High 51-304 Simjian 51281 ALEXANDER H. BRODMERKEL, PrimaryExaminer.

FRANK E. BAILEY, JOHN R. SPECK, MORRIS 10 LIEBMAN, Examiners.

R. W. DUCKWORTH, D. J. ARNOLD,

Assistant Examiners.

